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    <div class="refentry" id="glHint">
      <div class="titlepage"/>
      <div class="refnamediv">
        <h2>Name</h2>
        <p>glHint — specify implementation-specific hints</p>
      </div>
      <div class="refsynopsisdiv">
        <h2>C Specification</h2>
        <div class="funcsynopsis">
          <table style="border: 0; cellspacing: 0; cellpadding: 0;" class="funcprototype-table">
            <tr>
              <td>
                <code class="funcdef">void <strong class="fsfunc">glHint</strong>(</code>
              </td>
              <td>GLenum <var class="pdparam">target</var>, </td>
            </tr>
            <tr>
              <td> </td>
              <td>GLenum <var class="pdparam">mode</var><code>)</code>;</td>
            </tr>
          </table>
          <div class="funcprototype-spacer"> </div>
        </div>
      </div>
      <div class="refsect1" id="parameters">
        <h2>Parameters</h2>
        <div class="variablelist">
          <dl class="variablelist">
            <dt>
              <span class="term">
                <em class="parameter">
                  <code>target</code>
                </em>
              </span>
            </dt>
            <dd>
              <p>
                    Specifies a symbolic constant indicating the behavior to be controlled.
                    <code class="constant">GL_FRAGMENT_SHADER_DERIVATIVE_HINT</code>, and
                    <code class="constant">GL_GENERATE_MIPMAP_HINT</code>
                    are accepted.
                </p>
            </dd>
            <dt>
              <span class="term">
                <em class="parameter">
                  <code>mode</code>
                </em>
              </span>
            </dt>
            <dd>
              <p>
                    Specifies a symbolic constant indicating the desired behavior.
                    <code class="constant">GL_FASTEST</code>,
                    <code class="constant">GL_NICEST</code>, and
                    <code class="constant">GL_DONT_CARE</code> are accepted.
                </p>
            </dd>
          </dl>
        </div>
      </div>
      <div class="refsect1" id="description">
        <h2>Description</h2>
        <p>
            Certain aspects of GL behavior,
            when there is room for interpretation,
            can be controlled with hints.
            A hint is specified with two arguments.
            <em class="parameter"><code>target</code></em> is a symbolic
            constant indicating the behavior to be controlled,
            and <em class="parameter"><code>mode</code></em> is another symbolic constant indicating the desired
            behavior. The initial value for each <em class="parameter"><code>target</code></em> is <code class="constant">GL_DONT_CARE</code>.
            <em class="parameter"><code>mode</code></em> can be one of the following:
        </p>
        <div class="variablelist">
          <dl class="variablelist">
            <dt>
              <span class="term">
                <code class="constant">GL_FASTEST</code>
              </span>
            </dt>
            <dd>
              <p>
                    </p>
              <p>
                        The most efficient option should be chosen.
                    </p>
            </dd>
            <dt>
              <span class="term">
                <code class="constant">GL_NICEST</code>
              </span>
            </dt>
            <dd>
              <p>
                    </p>
              <p>
                        The most correct,
                        or highest quality,
                        option should be chosen.
                    </p>
            </dd>
            <dt>
              <span class="term">
                <code class="constant">GL_DONT_CARE</code>
              </span>
            </dt>
            <dd>
              <p>
                    </p>
              <p>
                        No preference.
                    </p>
            </dd>
          </dl>
        </div>
        <p>
            Though the implementation aspects that can be hinted are well defined,
            the interpretation of the hints depends on the implementation.
            The hint aspects that can be specified with <em class="parameter"><code>target</code></em>,
            along with suggested semantics,
            are as follows:
        </p>
        <div class="variablelist">
          <dl class="variablelist">
            <dt>
              <span class="term">
                <code class="constant">GL_FRAGMENT_SHADER_DERIVATIVE_HINT</code>
              </span>
            </dt>
            <dd>
              <p>
                    </p>
              <p>
                        Indicates the accuracy of the derivative calculation for the GL shading language fragment processing built-in functions:
                        <code class="constant">dFdx</code>, <code class="constant">dFdy</code>, and <code class="constant">fwidth</code>.
                    </p>
            </dd>
            <dt>
              <span class="term">
                <code class="constant">GL_GENERATE_MIPMAP_HINT</code>
              </span>
            </dt>
            <dd>
              <p>
                        Indicates the quality of filtering when generating mipmap images with
                        <a class="citerefentry" href="glGenerateMipmap.xhtml"><span class="citerefentry"><span class="refentrytitle">glGenerateMipmap</span></span></a>.
                    </p>
            </dd>
          </dl>
        </div>
      </div>
      <div class="refsect1" id="notes">
        <h2>Notes</h2>
        <p>
            The interpretation of hints depends on the implementation.
            Some implementations ignore <code class="function">glHint</code> settings.
        </p>
      </div>
      <div class="refsect1" id="errors">
        <h2>Errors</h2>
        <p>
            <code class="constant">GL_INVALID_ENUM</code> is generated if either <em class="parameter"><code>target</code></em> or <em class="parameter"><code>mode</code></em> is not
            an accepted value.
        </p>
      </div>
      <div class="refsect1" id="versions">
        <h2>API Version Support</h2>
        <div class="informaltable">
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                <th style="text-align: left; border-right: 2px solid ; ">
                 
            </th>
                <th style="text-align: center; border-bottom: 2px solid ; " colspan="2">
                <span class="bold"><strong>OpenGL ES API Version</strong></span>
            </th>
              </tr>
              <tr>
                <th style="text-align: left; border-right: 2px solid ; border-bottom: 2px solid ; ">
                <span class="bold"><strong>Function Name</strong></span>
            </th>
                <th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">
                <span class="bold"><strong>2.0</strong></span>
            </th>
                <th style="text-align: center; border-bottom: 2px solid ; ">
                <span class="bold"><strong>3.0</strong></span>
            </th>
              </tr>
            </thead>
            <tbody>
              <tr>
                <td style="text-align: left; border-right: 2px solid ; ">glHint</td>
                <td style="text-align: center; border-right: 2px solid ; ">✔</td>
                <td style="text-align: center; ">✔</td>
              </tr>
            </tbody>
          </table>
        </div>
      </div>
      <div class="refsect1" id="Copyright">
        <h2>Copyright</h2>
        <p>
            Copyright <span class="trademark"/>© 1991-2006 Silicon Graphics, Inc.
            Copyright <span class="trademark"/>© 2010-2014 Khronos Group.
            This document is licensed under the SGI Free Software B License.
            For details, see
            <a class="link" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
        </p>
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